Resin containers and paper containers for tightly sealed packaging of liquid food have a wide range of applications because of their adequate strength and lightness.
However, because resin containers and paper containers have a higher oxygen permeability than metal cans, the flavor of the contents of such containers undergoes degradation, thereby creating a short quality preservation period and other related problems.
Thus, in order to extend quality preservation period, an oxygen barrier resin such as ethylene-vinyl alcohol copolymer or the like is provided in the case of resin containers, and in the case of paper containers, containers are developed in which a paper base material is laminated by an aluminum foil, an oxygen barrier resin such as ethylene-vinyl alcohol copolymer, polyvinylden chloride resin or the like, or a resin film on which an inorganic oxide such as silica is deposited. Such containers are used for storage of liquid food.
Further, oxygen absorbing containers have been proposed in which an oxidation catalyst such as cobalt stearate or the like, iron powder and a reducing organic compound are included in the resin layer and bonding layer that make up the laminate.
However, in the container laminated by oxygen barrier resin, the blockage of oxygen is not complete, and in the container laminated by aluminum foil and resin film on which inorganic oxide is deposited, microscopic cracks (pin-holes) can occur during the lamination and molding process, thereby easily degrading the oxygen gas barrier property.
Further, in the case where iron powder is included, a significant increase in weight is required in order to obtain adequate results, and this makes it impossible to achieve a light-weight container. Moreover, there also exists sanitary problems. Sanitation problems as well as control over catalyst function also exist when an oxidation catalyst is used.
Moreover, difficulty arises in the case where a reducing organic compound is used because it is necessary to use a safe compound and care must be taken with regards to the heat resistance of the organic compound and the elution from the resin layer.
It is an object of the present invention to provide a resin composition and a laminate which contain a reducing organic compound and which make it possible to safely package and storage liquid food for a long period.